Dieting makes you fat:" Old wives tale or scientific fact?
'Dieting makes you fat.' On the surface, this assertion seems counterintuitive. After all, dieting for weight loss usually involves calorie or carbohydrate reduction; restricted eating; eating by certain 'rules;' and/or exercise. This usually results in weight loss in varying degrees for the dieter. Yet most dieters gain the majority of the weight they lose back. The lack of success of most popular 'diets' has caused many people to assert that dieting 'makes' the dieter fat, based upon metabolic damage combined with the psychological deprivation that dieting causes. This paper will argue that, given the weight of the evidence, although the physiological evidence is inconclusive that dieting itself leads to weight gain due to metabolic damage, there is substantial evidence that dieting can lead to a negative relationship with food that causes weight gain in the long run.
"A decreased rate at which the body burns calories; more fat and less muscle tissue; a greater preference for fatty foods; more difficulty losing weight the next time around; an increased risk for heart disease and diabetes; even premature death. Those are just some of the hazards researchers have theorized may result from yo-yo dieting, the losing and regaining of the same pounds many times over the years" ("Theories on yo-yo dieting unwind," Tufts University Diet & Nutrition Letter, 1994). Studying metabolic rates between dieters and non-dieters can be challenging, because it would not be ethically acceptable to force someone to gain and lose weight repeatedly over the course of many years. However, descriptive research studies do indicate a correlation between lower metabolic rates and 'extreme' dieting.
One study of 163 non-Hispanic white women which measured "dietary restraint and disinhibition found that members "who reported dieting at study entry were heavier at study entry and gained more weight over time than did nondieters. Finally, a significant interaction between restraint, disinhibition, and dieting showed that restraint moderated the effect of disinhibition on weight differently in nondieters than in dieters" (Savage, Hoffman & Birch 2012). For individuals actively not dieting or trying to lose weight, restraint was associated with lower body weights but with dieters, higher body weights were associated with attempts at restraint, indicating that dieting encouraged a fast and feast binge cycle (Savage, Hoffman & Birch 2012).
However, critics of the thesis that 'dieting will make you fat' point out that another problem with research on chronic dieters is that with every diet, the dieter becomes older, and with age, muscle mass decreases in proportion to fat, and metabolism slows even amongst normal weight dieters. There is evidence that "repeated dieting causes a rise in the proportion of body fat to lean muscle tissue failed to account for the fact that over the years people tend to put on more fat and lose more muscle" ("Theories on yo-yo dieting unwind, " Tufts University Diet & Nutrition Letter, 1994). Apparent difficulties with losing weight might be due to the fact that dieters are getting older with each successive diet, which is why it may seem as if it is harder and harder to lose weight with age.
A meta-analysis of 43 separate studies of the topic was proven to be inconclusive. Overall, "most studies evaluating the influence of weight cycling on metabolism showed no adverse effects on body composition, resting metabolic rate, body fat distribution, future successful weight loss, or risk factors for cardiovascular disease" but there was an association between extreme "weight variation and increased mortality and morbidity" ("Yo-yo' dieting may not be a problem," HealthFacts, 1995).
Even more significantly in support of the idea that 'dieting makes you fat,' comparative studies of adolescents and young adults who are not suffering from age-induced muscle loss, slowed metabolism and increased body fat composition indicated that dieters gain weight over time. One study of wrestlers found that wrestlers who frequently engaged in weight restriction and severe yo-yo dieting not only weighted more but had lower metabolic weights, pound for pound, than wrestlers who did not actively control their intake. It is true that "the study did not determine whether the yo-yo dieting reduced the wrestlers' calorie-burning ability or whether they burned fewer calories than the non-cyclers to begin with -- and therefore needed to diet more often to 'weigh into' their desired weight category" ("Theories on yo-yo dieting unwind," Tufts University Diet & Nutrition Letter, 1994). In other words, wrestlers who struggled to make weight might have slower metabolisms than those who were 'naturally' thin, or naturally close to their desired weight category.
But a similar finding was true of a study of adolescents in general. In one longitudinal study of 1,902 young adults throughout middle school, high school, and adolescence, frequent dieting indicated greater BMI increases vs. non-dieters as they matured. "For example, females using unhealthy weight control behaviors at both Time 1 and Time 2 increased their BMI by 4.63 units as compared with 2.29 units in females not using these behaviors" (Amber & Standish 2012). Interestingly, for girls, both healthy dieting and unhealthy weight control behaviors were associated with long-term weight gain, while for boys, "the picture was less clear-cut" and unhealthy strategies of regulation (such as fasting) were found to be associated with weight gain (Amber & Standish 2012). Once again, it is possible to postulate that those teens at-risk for higher BMIs might be more prone to dieting than non-dieters, although the finding that only boys who used unhealthy 'crash dieting' to curtail BMI suggests that there may be something particularly damaging about radical weight reduction strategies. Also, girls, even those who did not use unhealthy weight control behaviors, might be more prone to chronic dieting to fit unrealistic cultural expectations, given that there is greater cultural pressure for females to be thin than for males.
In general, the fact that adolescents who begin dieting show significantly higher weights than those who did not diet while young combined with existing research on adults tends to support the notion that dietary restriction over time decreases metabolism and increases weight gain. At very least, a strong correlation has been established between dieting and weight gain, indicating that traditional diets are ineffectual as a means of weight control, as opposed to less extreme modifications to make diets more healthy and to introduce more physical activity. Dieters themselves often report extreme hunger when restricting, even though their metabolisms are said to have slowed. The reasons for this statistic are unclear. Weight regulation is a little-understood phenomenon, and there is some evidence that dietary regulation can interfere with the "feedback loop between fat depletion" given that studies indicate that "human subjects recovering from starvation continue to overeat well after body fat has been restored to pre-starvation values, thereby contributing to 'fat overshooting'…feedback signals from both fat and lean tissues contribute to recovering body weight through effects on energy intake and thermogenesis, and that a faster rate of fat recovery relative to lean tissue recovery is a central outcome of body composition autoregulation that drives fat overshooting" (Dulloo, A., Jacquet, J., & Montani)
However, even if yo-yo dieting may not physically slow down the metabolism, it has been suggested that the psychological profile of constant dieting and deprivation seems to extract a hefty toll. Psychological effects include a loss of self-esteem and a constant sense of failure. But once again, causality vs. causation is debatable to some extent. It "could be that remaining at a stable weight is a sign of general psychological well-being, whereas weight cycling results from emotional distress rather than causes it" (Theories on yo-yo dieting unwind, 1994, Tufts University Diet & Nutrition Letter).
Regardless, the psychological distress associated with rapid weight changes and the fact that dieting does not seem to lead to the desired modification of body weight and…